Added another version of `nk_tree` that does not store internal state
to hold the tree state (minimized/maximized). Main advantages is
possibily less memory consumptions and more user control.
In addition a new set of button overloads were added to directly pass
in a button style struct which allows an easier way to have custom
button visuals for specific buttons.
Added additional `nk_group` version which uses an external scrollbar
offset instead of internally managing the memory. In addition
`nk_list_view` is introduced which allows drawing huge lists inside a
`nk_group`(#269).
I simplified a lot of API calls by pulling panel memory management
inside the library. All API calls which previously required a panel
as parameter are now handling their panel themself.
Previously every widget border was drawn by two overlapping rectangles
to limit the number of primitives required to be supported by any
potential backend. The biggest problem from using this approach
is drawing overhead and no real way to get widget transparency. So
I changed border drawing to use stroked rectangles instead of a
second filled rectangle drawing call.
calling nk_init_default stores the address to the font (which is on stack) into the nk_context
but when it returns that stack memory is effectively undefined, thus making the program segfault
using memcmp and decide whether to draw a new frame or not:
* added NK_ZERO_COMMAND_MEMORY macro
* when NK_ZERO_COMMAND_MEMORY is defined, inside
nk_command_buffer_push function there is an additional call
to NK_MEMSET after allocating memory for new drawing command
For more information please look inside the changelog. This is more of
an internal fix and hopefully does not break any existing code. I also
removed `nk_strfmt` from the API and made it internal only.
